Process of increasing the intensity of incandescent light.



R. P. PIGTET. PROCESS OF INCREASING THE INTENSITY OF INGANDESGENTLIGHT.,

APPLIGATION FILED 3111.19, 1904.

1,026,121. PatentedMay14,19l2.

2 SHEETS-SHEET 1.

. PIGTET. PROCESS OF INCREASING THE INTENSITY 0F INGANDESGENT LIGHTAPPLICATION FILED JAH.19 1904, v1,026,121. I

2 SHEETSBHBET 2.

COLUMMA PLANOdIlAPH CD." WASHINGTON, D- C- tube (Figs. 3, 4, 5 and 6).

UNI

ED STATES PATENT OFFICE.

RAO'UL PIERRE PICTET, OF BERLIN, GERMANY, ASSIGNOR TO THE FIRM OFSAUERSTOFF-INDUSTRIE AK'IIENGESELLSGHAFT, OF BERLIN, GERMANY.

PROCESS OF INCREASING THE INTENSITY F INGANDESCENT LIGI-IT.

Specification of Letters Patent.

Patented May 14-, 1912.

Application filed. January 19, 1904. Serial No. 189,775.

To all whom it may concern:

Be it known that I, RAOUL PIERRE PIGTET, professor and doctor ofphilosophy, 9. citizen of Switzerland, residing at and whose post-officeaddress is 2 WVattstrasse, Berlin, Prussia, German Empire, haveinventednew and useful Improvements in Processes of Increasing the Intensity ofIncandescent Light, of which the following is a specification.

In the accompanying drawing Various constructional forms of burner forcarrying the invention into practice are illustrated in longitudinalsectional view.

Figures 1 and 2 show a burner with one incandescent mantle. Figs. 3 to 7with two incandescent mantles.

Similar letters refer to similar parts throughout the several views.

a is the gas conduit, 6 the oxygen conduit, 0 the incandescent mantle,(Z the air supply openings for a'Bunsen burner.

The incandescent mantle may be so arranged that it surrounds theexterior burner It may also be placed within the area inclosed by theexterior burner tube. (Figs. 1, 2, 3 and 4). In

the arrangement illustrated in Fig. 5 a gauze of refractory oxidsurrounds the exterior burner tube, a second tube being concentricallyarranged in the mixing tube. In the arrangement illustrated in Fig. 7within the said second tube a further gauze of refractory oxid isarranged.

The object of this invention is to permit of the practical utilizationof the known Stephan-Boltzmann law of radiation in connection with theincrease of the light emission by heating a body to a far greater extentthan has hitherto been effected technically. As is known, the totalradiation of a heated body increases in a measure lying between thefourth and fifth power of the absolute temperature of the incandescentbody. On the other hand the practical experiments and theoreticalcalculations of Kurlbaum, IVien, Pringsheim, Lummer and others show thatthe displacement of the radiation energy maximum toward the blue side ofthe spectrum takes place rapidly, so that the visible radiation actuallytakes place on an average to the twelfth power of the absolutetemperature.

By means of the method or process which forms the subject of thisinvention it is possible to bring a body which is per so an illuminantbody, such for example as nets or rods of the known common and raremetallic alkaline earths, into the hottest zone of a flame which is ofitself extremely hot, and thereby heat the net or the like in such amanner that the light emitted by it is far greater than it is possibleto attain by other means. Although it is not possible for obviousreasons to obtain in practice results equal to theoretical calculations,under certain conditions a luminous efiiciency is obtained whichapproximates fairly closely the theoretical efficiency. The process maybe carried into practice in various ways.

1. The first method consists in conducting within an incandescent bodycombustible gas rendered non-luminous by a Bunsen burner or other means,while externally oxygen or air rich in oxygen is led over theincandescing body.

2. In accordance with the second method the air or the oxygen isconducted within the said incandescing body while the combustible gas isled over it.

3. In a third method, which constitutes a combination of the first two,the air or oxygen is conducted by means of a concentric slit in such amanner that the oxygen flows in between two atmospheres of gas so thatan extremely intimate mixture of the oxygen and the gas takes placeoutside the burner.

4. A fourth method consists in passing a second mantle over the first,gas being con ducted within the inner mantle and oxygen into the spacebetween. the two mantles.

5.11 fifth method consists in admitting oxygen within the innerincandescing body and combustible gas into the space between the twoincandescing bodies.

(3. A' sixth method is a still further extension of the process and isbased upon the provision in the method No. 5 of an additional atmosphereof oxygen through suitable tube slots or holes, whereby the outer mantleis caused to fulfil the same function as the incandescent body in method1, by which means two superposed bright illuminating nets are obtained.Notwithstanding the fact that in accordance with Kirchhoffs and Bunsenslaws a portion of the radiation of the inner incandescent body isabsorbed by the mass of the outer body, the interstices of the outer netstill permit of the passage of so much light that increased illuminatingpower is obt-ained. It is, however, possible to so select thecomposition of the incandescing bodies having regard to the saidfundamental physical law, that they emit different light, that is to saylight of a different wave length, so that by selecting totally differentelements, the whole of the radiant energy may be permitted to escape.

The essential feature of the novel method consists, in addition to theappropriate constructions of the burners which are illustrated in theaccompanying drawing, more particularly in the fact that these samearrangements result in an almost constant contact of oxygen or air uponone wall of an incandescent body and combustible gas on the other wall.Further, the construction of the gas supply-passages is such that theypermit of the issue of the gases under pressure in concentric superposedcylinders. If two gases differing from each other to such an extent andcoming from two different sides meet on the wall of an incandescentbody, it is obvious that the hottest point of the flame formed willnecessarily be found at the meeting point. On the other hand the factthat in the other burners for example a cylinder of oxygen is surroundedby a hollow cylinder of gas, both of which flow to meet each other inthe same direction or at an acute angle, causes an incandescent bodysituated in the contact surface to likewise be in the hottest part ofthe flame. The gases are sent under diflerent pressures from the pipesin longitudinal directions. In other words the velocities of the gasstreams are different. By the movement of the gas streams a suctionaction is exercised. This suction action sucks the gas from the one sideto the opposite side. l Vith reference to the fact that the two gasesare subjected to a certain pressure in a 1011- gitudinal direction, thegases are prevented from spreading out. The main amount will have theoutline of the mantle. A mixture of the gases will only occur at thosepoints Where they are in direct connection. The chief amount of thegases follows however the outline of the mantle. This is due to thedifference of the pressure under which the gases are handled.

The novel process also differs from known burners in which air and gasmingle together in a tube owing to the fact that here (as alreadystated) the gases issue separately. The burners are, however, alsodifferent from the usual oxy-hydrogen burners to the extent that thelikewise novel multiplication of the blast action is attained by thesaid cylindrical gas outlet tubes with the assistance of a very simpledevice.

A further characteristic feature of the novel process consists in thefact that all the arrangement described tend to the production of thephenomenon that by suitably differentiating the gas pressure the gaseswill to a certain extent come in contact with each other only where anopening in the mantle is situated, so that each of these openings actsas a gas blast aperture, which finally results in enabling the limitingsurfaces of these small openings to withstand the highest possibletemperature of the flame. The novelty of the process also resides in thefact that contrary to what is the case with previous inventions, inwhich reliance is placed upon thecapacity for suction of the flame(which is extremely defective), the oxygen required to supportcombustion and for producing the highest temperature is introduced in aconduit and under pressure at the place at which it produces thegreatest effect. As already stated the combustible gas is employed in anon-liuninous condition, and it is immaterial whether this is attainedby mixing the gas with air in a Bunsen tube or whether oxygen alone isforced under pressure into the mixing tube, in which latter case Davygauzes for preventing the flame from lighting back must be employed. Itis unimportant whether these gauzes are suspended above the burners orextend within them.

hat I claim, and desire to secure by Letters Patent of the UnitedStates, is 4 The process for increasing the intensity of incandescentlights, which consists in conducting streams of nonluminescenthydrocarbon gas and oxygen in the same vertical direction underdifferent pressures to opposite sides of the mantle, and in contact withthe said surfaces of the mantle, the height of the pressures being sochosen that the stream of increased pressure upon one side of the mantledraws by its movement the stream of lesser pressure upon the other sideof the mantle through the meshes or openings of the mantle.

In witness whereof I have hereunto signed my name this twenty-fifth dayof November, 1903, in the presence of two subscribing witnesses.

RAOUL PIERRE PICTET.

Witnesses:

JEAN LEUGEISE, Hanson G. Coxn.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

